1. Field of the Invention
The invention relates to a method and associated apparatus applied to a receiver of a wireless network, and more particularly, to a method and associated apparatus capable of determining an unknown quantity of antennas of a transmitter according to a network signal received at a receiver.
2. Description of the Related Art
A wireless network, which performs exchange, interconnection, communication and/or broadcasting of packet, data, message, command, audio and video streams by network signals via wireless transmission, is one of the most important network techniques in modern communication technology. Among the various wireless network techniques, multi-input multi-out (MIMO) is a focus of research and development. Reasons contributing to such importance of the MIMO technique are that, without occupying additional bandwidth, the MIMO technique is capable of increasing a network capacity and data transmission rate, reducing bit error rate, strengthening interference resistance, improving directivity through beamforming and/or reinforcing resistance against channel attenuation. For example, the wireless local area network based on the IEEE 802.11n specification has incorporated the MIMO technique. In a MIMO wireless network, one transmitter may be provided with multiple antennas, each sending corresponding single-antenna signals. Network signals received at a receiver are synthesized from the single-antenna signals. Similarly, one receiver may also be provided with one or multiple antennas to receive the network signals transmitted from the transmitter.
Since the network signals transmitted from the transmitter may be transmitted by one or multiple antennas, the receiver is unaware of the quantity of antennas at the transmitter when first receiving the network signals. The sooner the receiver determines the quantity of transmitting antennas at the transmitter, the more quickly the information carried in the network signals can be parsed. Therefore, it is critical that the receiver be able to correctly determine the unknown quantity of transmitting antennas according to the received network signals.